Root cause insight into the common BMW blower motor resistor failures

Actually, I was remiss in not stating that the blower motor generally
fails by acting weirdly, often said to "have a mind of its own", and,
most often by a parasitic current draw overnight that kills the battery.

But anyone who thinks they are somebody or something needs to own at
least ONE weiner wagon - mabee two or 3 - one of each major brand -
MB, BMW, and Audi - and perhaps a Porsche - just to prove they are not
invulnerable and all powerfull. Either one of them can take a guy
down a notch pretty quickly.

Not unless you want to become addicted and need to drive kraut burners
for the rest of your life. I and several friends have unfortunately
fallen prey to this disease and our wallets have suffered as a result.
nate

That seems like an EXCELLENT idea, if we can put some kind
of temperature indicator in the FSU tines, then we can observe
what the temperature is in situ - which might tell us something
about what is overheating these things (assuming heat is the culprit).

I had a dodge caravan that fried its heater AC motor speed control
resistor repeatedly....
the connector to the wiring harness detoriates from the high current
and the voltage drop causes the connector to heat up and the entire
assembly fails.
Oddly enough I repair roll laminators that apply plastic film to paper
think menus:)
laminators experience similiar failures so I did the following.
Purchased a new resistor block, soldered wires on all the connectors
putting a heavy wire on each one.... Put a pigtail on each one.
Installed resistor block. Its screwerd to the fire wall.
Cut the plug assembly off the harness, stripped all wires, twisted
them together and installed wire nuts on each one.
had the van for years with zero problems for this part:)

I don't have a link, but we had the blower resistor widget
go on an X5 here. And the aux cooling fan motor has gone
twice. There are plenty of threads online about many people having
those problems. Oh, and don't forget the
nice X5 feature where the cable that they use to hold up the
windows snaps, sending the window crashing down inside
the door, breaking it into a million pieces. Had that happen
twice too, once while the car was just sitting in the driveway.
Other time was driving down the highway.
Then there are their defective rubber parts. Like the boot on
the intake manifold that cracks in just a few years. Or the
CV joint boots. I've had lots of cars with CV boots and
only on the X5 do they fail every 20K miles. I've seen Honda CRVs
that went 200K miles with no failure.

As for me, I fell sway to all the people saying how great the bimmer was.
It was only after I owned it, that I realized that BMW engineers knew
how to design a suspension and a drive train, but they had no idea
how to build a machine.
To their credit, some people say it's not the engineers fault as
they probably know by now that every single Bosch 5.7 ABS control
module fried in every one of the vehicles it was placed in, and that
the final stage unit cooked itself to death in every single BMW it
was ever placed in, and that the 2-bar plastic cooling system
sprang a leak on almost every single BMW ever built, etc.
In fact, there's absolutely NO WAY BMW can't know about these
egregious engineering flaws. So, the common conclusion is that
their customers don't care - so why should they.
To me, it smacks of 3rd-grade engineering from BMW, so, that's why
I, for one, am amazed (being an owner myself), how sophomoric BMW
engineering really is.
Disclaimer: Yet, the drive train is phenomenal!

Maybe it's time to look at this thing like gas and brakes...
You put gas in, you go so far. You put one of these
blower modules in and you go for a few years again.
It's not like they are a $500 or $1000 puter. Don't they
cost like $50? I mean how much is time worth trying
to reverse engineer it.....

This is how people are. At some point intellectual curiosity takes over.
In this case it might actually be worth it, because of the sheer number of
the things out there that are failing.... one person figuring the failure
mode out might save a lot of people that grief.
But mostly it's just intellectual curiosity.
--scott

Like I said before, don't drive one then. It's kind of like going on a
date with that unbelievably attractive female type who is also smart,
witty, fun to be around, actually seems to like you, and oh by the way
is completely mentally unhinged.
Suddenly you find yourself putting up with all sorts of stuff that you
wouldn't, otherwise... (now that said, touch wood, current ride has
exhibited none of the known issues... which reminds me, I need to call
and schedule the battery cable recall @ the stealership)
nate

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